Talk:Momentum Equation
You need a third non-website source *Use inline citations throughout your article to show where you pulled information from *Add in categories to help sort your page within the greater wiki *Why aren't the viscous forces included in an integral? *Why is the surface force negative? *What do the variables mean in your equations? *Do we have to make any assumptions in this derivation? *When is the momentum equation appropriate to use? (Give general conditions rather than specific cases? --Wengler 23:23, September 30, 2009 (UTC) Wengler pretty much summed it up. You need to define what all the symbols in your equations mean. Also give more examples of using this equation in aerodynamics, for example calculating lift and drag, not just thrust. -- Matt Daskilewicz Review by Jonathan Herault The whole article seems complete and pretty good. However, there are some minor problems that must corrected: Derivation and description 1) What is "the control volume"? I think here, without loss of generality, you can speak of any kind of CV. 2) In body forces, maybe you should specify that f is a volume force, and put it in bold (it's a vector) 3) All your elementary surfaces dS are vectors! Don't forget to put them in bold. 4) Your sentence "it is always possible to wrap the control surface around the body in such a fashion that the body is always outside the control volume." is quite obscure. I don't understand how you can wrap the CS around the body such that it's no longer inside the CS!? Moreover I couldn't understand the whole point of this paragraph. You may re-phrase it to make it more clear. 5)I suppose there is a mistake in the sentence "there would be additional force on the fluid-the equal and opposite..." 6) For the change in momentum paragraph, I think that you could also quote the Reynolds transport theorem (aka the PICO rule : Production + Input = Change + Output). It's up to you but to me it sounds more academic. Application to an acft engine. It was a good idea, however: 7)The formulation "everything that relates" seems to vague to me. You may be more specific. 8)Why does the fuel flow \dot{m_f} vanishes? 9) This example makes me think of the frequently encountered equation \mathbf{F}=\dot{m}\Delta\mathbf{V} . You should talk about it! blb 10) I think you must precise the conditions where it is more appropriate to use this formulation of the momentum equation. It could be done at the beginning of the paragraph derivation and description. 11) Your images miss sources and licensing Review by Sang-in Park I am sorry that I am late. You make a good article, but there are some problems. 1) In the part of Definition, you focus the mometum equation on a fluid. However, The equation generally satisfied all of continuum materials(solid and fluid).Thus, I think it may extend to continuum materials. 2) In addition, there are two type of momentum equations- Linear momentum and Angular momentum. Therefore, I should mention these two type of momentum equation. 3) In the part of Derivation and Description, you state all derivation of equation under assumption of fluid. However, as I mentioned above, you may mention general form of equation and then focus on fluid for applying to aerodynamics. I will leave more at later time. ** the 1st inline citation done properly. with the rest some editing issues are there. ** this is just my curiosity, doesnt NS equation holds for both liner and non-liner momentum ? just that we need to express it in the rotational form ? ** the 2nd paragraph under the "change in momentum' heading, seems not so correct. probaly you were describing the left hand side of the equation, not the rhs. ** overall, very nicely done article, suitable for graduate level students having exporuse to fluid mechanics. --Fahmed7 01:29, October 23, 2009 (UTC)faisal